Carbureter.



GTE. woke.

cmunmn. APPLICATION FILED IAN. 8'19I3- RENEWED IUNE I- I9l8. 1,291,040.

' Patented Jan. 14,1919.

' 2'SHEETSSHEET I.

STATES PATENT OFFICE.

CHARLES E. LUCKE, OF NEW YORK, N. Y., ASSIGNOR TO GAS AND OIL COMBUSTION COMPANY, OF NEW YORK, N. Y;, A CORPORATION OF DELAWARE.

Specification of Letters Patent.

Patented Jan. 14, 1919.

Application filed January s, 1913, Serial No. 740,885. Renewed June 1, 1915. Serial No. 237,819.

To all whom it may concern:

Be it known that I, CHARLES E. LUCKE, a citizen of the United States, residing at New York city, in the county of New York and State of New York, have invented certain new and useful. Improvements in Carbureters, fully described and represented in the following specification and the accompanying drawings, forming a part of the same.

This invention'relates to carbureters and more particularly to a carbureter which is adapted to sustain a continuous flow of explosive mixture when required and to supply the explosive mixture under any desired pressure. The invention aims to provide an improved carbureter adapted to sustain a flow of an explosive mixture of constant or substantially constant richness irrespective of variation in the volume or rate of flow; and the invention aimsmore especially to provide a carbureter adapted to supply the explosive mixture under pressure greater than atmosphere, and to maintain the proportions or richness of the mixture so supplied constant or substantially constant irrespective of variations in the volume or rate of flow, and irrespective also of variation in tlie pressure with'which the mixture is sup ied. p The invention includes means whereby, under varying rates of air flow through the carbureter and under variations inpressure, the supply of fuel to the mixing chamber of the carbureter is automatically maintained proportionate to, or substantially proportionate to, the amount of air passing therethrough. The invention has been embodied in a carbureter of the constant level type,

that is, of the type in which the volatile liquid fuel is maintained at a constant level in a receptacle from which it passes into the mixing or carbureting chamber. While not necessarily'limited in all its features to a carbureter of this type, the invention includes means whereby in a carbureter of this type increase or decrease in the pressure in the mixing chamber of the carbureter is accompanied by an increase or decrease respectively of the pressure on the liquid in the fuel receptacle; and means whereby the relation between the pressure in the mixing chamber and the pressure in the fuel receptacle under which the fuel liquid flows to the mixing chamber is automatically conto flow to the mixing chamber. The invention' comprises, further, means for automatically controlling this difference or variance between the pressure in the mixing chamber and the pressure on the liquid in the fuel receptacle whereby it is so varied with variations in the air flow as to cause the fuel to be supplied to the mixing chamber in amount proportionate to, or substantially proportionate to, the amount of air passing therethrough. The invention includes also other features of construction and combinations of parts hereinafter described and particularly set forth in the claims.

An understanding of the invention can best be given by a detailed description ofa carbureter embodying the various features of the invention in a preferred form in connection with drawings showing such a preferred embodiment of the invention, and such a description will now be given in connection with the accompanying drawings, in which:

Figure" 1 is a centralvertical sectional view of a carbureter made in accordance with my invention, parts being shown .in elevation;

shown diagrammatically.

Referring to the drawings, in the form of carbureter shown, I provide a tank or receptacle 10 to which the volatile liquid fuel is supplied through a conduit 11, suitable means for maintaining a constant level of the liquid in the tank 10 being provided, as, the usual float 12 in the tank connected to actuate a valve 13 for controlling the supply of fuel liquid to the tank. Communicating" with the tank 10 through a. passage 14, is an outlet or nozzle 15, the discharge end of which extends a little above the normal level of the fuel liquid in the tank, and the flow from which is controlled by an adjustable needle valve 18. The nozzle discharges into a mixing passage or chamber 16 which communicates with an ofitake pipe 17. The tank 10 is conveniently made of annular form with its inner walls forming the walls of the mixingpassage or chamber located centrally of the tank, the nozzle extending upward axially of the mixing chamber and terminating at a point intermediate the top and bottom thereof. The supply passage 14 is shown as bridging the lower part of the mixing chamber, opening at each end to the tank 10 and leaving an opening or passage way 19 on each side through which air is supplied to the mixing chamber. To secure a better carbureting action, the mixing chamber or passage is constricted adjacent the discharge end of the nozzle, as at a, so as to converge the air column and cause a stronger flow across the discharge edges of the nozzle. The tank 10 is mounted within a casing 20 which provides an air chamber 21 between its walls and the tank and with which the mixing chamber communicates through the openings or passage ways 19. There is no special object aside from convenience in construction and symmetry in design in providing an annular air chamber, but it is desirable because of its steadying action on the operation of the carbureter to provide an air chamber of comparatively large size. The tank 10 is in constant communication with the air chamber 21 through a port 27 whereby the pressure on the liquid in the tank will always be that of the air in the chamber 21. This port may also serve as an overflow outlet for the tank 10. Air is supplied to the carbureter through a supply pipe 25 communicating with any desired source of supply of air under suitable pressure and opening into the air chamber 21 preferably at a point directly beneath the mixing chamber 16. The supply pipe is provided with a throttle valve or damper 26 for controlling the supply of air to the carbureter and the amount and pressure of the combustible mixture passing from the carburetor through the otftake 17.

The passage of the fuel liquid from the ank 10 through the nozzle into the mixing passage or chamber 16 when the carbureter is in operation is secured by maintaining a difference in he pressures in the mixing chamber and on the liquid in the tank 10. For securing such difference in pressures with the pressure in both places depending upon the same source or supply of air, I provide pressure reducing means for reducing the pressure in the mixing chamber below that exerted on the liquid in the tank 10. To provide such pressure reducing means, I

form the carbureter with a restricted orifice between the mixing chamber and the immediate source of supply, the air chamber 21 in the construction shown. This orifice should be of such relative size as to offer sufiicient resistance to the flow of air therethrough to secure the necessary dro in air pressure to maintain the desired di erence between the pressures in the mixin chamber and in the tank 10. This orifice might be formed by the openings or passage ways 19 about the supply passa e 14 in the construction shown, but I pre erably provide a partition or bottom plate 28 below the passage ways 19 having an opening or port '30 which forms the restricted orifice for causing the air to expand into the mixing chamber or passage to give the desired drop in ressure.

In order that the fuel liquid may flow into the tank 10 when the valve 13 is opened, it is necessary that the liquid be supplied to reach the valve under a ressure in excess of the pressure in the tan and to secure a uniform supply of the liquid to the tank under varying air pressures in the tank it is desirable that the excess pressure on the liquid in the supply passage 11 over the tank pressure be maintained constant. For varying the liquid supply pressure with variations in the air pressure in the tank 10, so that such excess pressure shall be maintained constanhl provide in the construction shown a closed tank or reservoir 31 which is connected with the air chamber 21 or tank 10 by a pressure equalizing pipe 32 100 and from which the fuel liquid is supplied through a pipe 33 connecting with the supply passage 11 of the carbureter, the tank 31 beingelevated sufliciently above the carbureter to cause the liquid to reach the valve 105 13 under the desired excess pressure.

When the carbureter is in use and air is flowing through the mixing passage or chamber 16, the air pressure in the air chamber 21 and tank 10 will be greater than 110 that in the mixing chamber, and this difference in pressure will cause the gasolene or other fuel liquid to rise in the nozzle 15 andbe discharged into the mixing chamber where it meets the air current passing the nozzle and is more or less completely vaporized therein, the mixture. thusformed then passing through the ofitake 17 to the place of use.

The quantity of air that will flow through the carbureter depends upon the supply pressure in the pipe 25 and the resistance at the ultimate outlet where the mixture burns and the intermediate resistances including the resistances encountered within the carbureter, which latter are not very great. Thus with a given supply pressure and a given setting of the damper 26, the amount of air that will flow through will depend almost entirely on the resistance beyond the reter, such for example as would be caused.-

/ by fixed orifices discharging to the atmosphere, increase of air flow will be secured by opening the damper 26 and decrease of flow by closing the damper. Because of the restriction between the air chamber 21 and the mixingchamber, change in the air flow changes the difference between the pressure in the mixing chamber and the pressure acting on the liquid in the tank 10, an increased flow causing an increase of this difference in pressures and a decreased flow lessening the difference in pressures.

The supply of fuel liquid to the mixing chamber through the nozzle 15 is primarily,

adjusted by means of the valve 18 to the quantity necessary to form with the amount of air passing the nozzle an explosive mixture of the desired strength or proportions, screwing the valve down decreasing the flow of fuel liquid and weakening the mixture, and screwing it up increasing the flow and giving a richer mixture. Having once set the valve to secure the desired proportions for some one rate of flow, the apparatus will operate to maintain such proportions and supply a mixture of substantially constant richness for other 'rates of flow resulting from moving the damper or throttle 26 or changing the supply pressure or changing the resistance beyond the mixing chamber, that is, as the air flow through the carbureter increases or decreases, the' amount of fuel liquid supplied to the mixing chamber will also be proportionately increased or decreased. For conditions involving an average air-flow through the carbureter widely different from that for which the nozzle valve has been set, it may be desirable for best results to reset the nozzle valve for a pressure difference approximating the pressure difference or the average pressure difference of the particular new condition of use; and it may sometimes be. desirable, also,

where extreme nicety in adjustment of proportions is desired to resort to the hand adjustment by means of the valve 18 to meet varying air-flows.

The automatic increase or decrease in flow of fuel liquid from the tank 10 through the nozzle into the mixing chamber with'an increase or decrease in the air flow through the mixing chamber results from the increase or decrease in the difference in pressures in the mixing chamber and the tank 10 or air supply chamber 21 which occurs with an increase or decrease in air flow through the carbureter as before pointed out, that is, when there is a comparatively large flow of air through the carbureter the pressure in the mixing chamber will be lower than that in the air chamber and tank 10 by a greater amount than for relatively smaller rates of air flow through the carbureter. 'While this variation in the difference in air pressures in the mixing chamber and in the fuel liquid supply chamber causes a variation in the supply of fuel liquid to the mixing chamber which results in maintaining under varying conditions of air flow a nearly constant proportion of fuel and air in the mixture leaving the carbureter, it is found that the supply or flow of fuel liquid to the'mixing chamber under the influence of this varying diflerencein pressures does not .vary exactly in proportion to the Variation in the air flow. With a carbureter having only the parts or features so far described, when the valve 18 is adjusted, for example, for comparatively small rates of flow, then as the flow is increased, as bv further opening the damper or throttle 26, the supply of fuel liquid to the mixing chamber also increases, but the increase in fiow of fuel liquid is somewhat faster or in excess of the increase in air-flow, so that after a comparatively high rate of air-flow has been establlshed carbureter is accompanied by an excessive v reduction in the supply of fuel liquid to the mixing chamber which may cause an appreciable weakening-of the mixture supplied by the carbureter.

portionate variation in the flow of fuel liquid to the mixing chamber under the influence of a varying air-flow through the carbureter, I provide means for by-passing air from the air supply on the tank side of the nozzle to the offtake or mixing. chamber, or the air space on the discharge side of the nozzle, and means for controlling such by- In order to compensate for such d1spro-" be suitably proportioned to the'variance in the difference in pressures at opposite sides of the nozzle 15. When the carbureter is provided with such an automatically controlled by-pass, when a high rateof flow has been established through the carbureter causing such an increase in the difference between the pressures in the mixing chamber and in the tank 10, or on the two sides of the nozzle, as results in a disproportionately increased flow of fuel liquid to the mixing chamber, then this increase in the difference in pressures will cause the lifting of one or more of the check valves 36 according to the amount of the increase in pressure difierence, and this lifting of the c eck valves has the result of bringing the proportions of fuel liquid and air in the mixture back to the desired proportions. The opening of the check valves restores the proportions in the mixture by a double actlon. The mixture passing out through the oiftake 17, which has an excessive amount of fuel, is diluted by the air passing from the chamber 21 through the valve ports directly to the offtake, and at the same time the opening of the check valves has the effect of reducing the excess of pressure in the air chamber 21 and tank 10 over that in the mixing chamber,

thereby reducing the driving force on the fuel liquid. In other words, the opening of .the check valves under excessive pressure difference which causes an excess flow of fuel liquid results in adding air to the too rich mixture and in reducin the flow of fuel to themixing chamber. lhe check valves also serve to minimize fluctuations in the quality of the mixture which might result from sudden increases in the air pressure on the supply side of the carbureter or sulden decreases in pressure on the delivery s1 e. I

The supply of fuel liquid to the mixing chamber is thus automatically controlled in my carbureter by causing the pressure on the fuel liquid in the tank or receptacle 10 to be increased and decreased with increase and decrease respectively of the pressure in the mixing chamber, thereby maintaining the desired flow under varying pressures in the system; by increasing and decreasing the difference in pressure between the mixing chamber and the tank 10 with increase and decrease respectively in air-flow through the mixing chamber, thereby maintaining the supply of fuel to the mixing chamber pro portionate, or approm'mately proportionate, to the amount of air passing through the mim'ng chamber; and by compensating for disproportionate variation in the pressure difference between the mixing chamber and the tank 10 which would cause disproportionate variation in fuel supply to the mixing chamber by means controlled by the pressure diiference and acting to modify the variations in such pressure difference, such means as shown operating to by-pass air from the air supply on the tank side of the nozzle to the ofitake or mixing chamber, or the air space on the discharge side of the nozzle.

It is apparent, therefore, that with my carbureter the proportions of fuel and air in the mixture delivered may for a wide range of air-flow be kept automatically within the explosive range and very close to the chemical combining proportions, so desirable for combustion. Any departure from the desired proportions in the mixture delivered due to failure to be absolutely correct in the automatic adjustment provided may be corrected by hand adjustment of the needle valve 18. 7

As an additional means for adjusting the proportions of fuel and air in the mixture delivered by the carbureter, the carb'ureter may, when desired, be provided with means, which in the carbureter shown is manually adjustable, for adjusting the size of the restricted orifice through which the air is caused to expand into the; mixing chamber.

Such adjusting means is shown in the draw- 1 of the port 30. Increasing the size of the port will decrease the reslstance offered to the air-flow therethrough and, therefore, decrease the difference in pressure between the mixing chamber and the air chamber and decrease the supply of fuel, and making the rt smaller will increase the resistance and lncrease the diiference in pressure and cause an increased flow of the liquid to the mixing chamber. The shutter 37 thus serves as a means for adjusting the difference in pressure between the mixing chamber and the tank '10, and, therefore, also as a means for controlling the flow of fuel liquid to the mixing chamber. It might thus serve the purpose of the needle valve 18, but such relative pressure controlling means is prefably employed in connection with the needle valve or its equivalent whereby the flow capacity of the nozzle is directly controlled, as I am thereby enabled to adjust the carbureter more suitably so as to secure more accurate automatic control of the supply of fuel under some conditions of use.

For operating with the less volatile fuel liquids, heating means may be provided for heating the fuel to cause it to volatilize more completely in the air with which it is mixed. Such heating means is preferably arranged to act on the mixture, rather than on the air or on the liquid before reaching the mixing chamber. As shown in Fig. 4 "of the drawings, the mixture is heated after leaving the mixing chamber by being caused to pass through a heater 40 (which is shown means may also be employed for operating with alcohol.

My carbureter is particularly adapted for use where a sustained flow of the mixture is required and where the mixture must be supplied under pressure at the point of consumption, and has been especially designed for use in supplying an explosive mixture t a fire bed in which localized and continuous combustion of the mixture is maintained. The carbureter may obviously, however, be applied to other uses for which it may be found suitable, and is adapted for supplying the mixture under practically any desired pressure, and to supply consuming apparatus requiring a discontinuous flow as well as one needing a sustained or continuous flow.

It is to be understood that the invention is not to be limited to the exact combination and arrangement of parts in the preferred construction shown in the drawings and to which the foregoing description has been lar ely confined, but that it includes changes an modifications thereof within the claims, it being apparent that the construction shown may be varied without departing from the spirit and scope of the invention.

What is claimed is:

1. An apparatus for supplying a continuous flow under pressure greater than atmosphere of an approximately uniform mixture of compressed air and the vapor of liquid .fuel, comprisin a mixing chamber having an air inlet an a mixture outlet, means for supplying compressed air to the mixing chamber through the air inlet, means for supplying volatile liquid fuel to the mixing chamber under a maintained pressure greater than the air pressure in the mixing chamber, means for increasing and decreasing the pressure under whichthe fuel liquid is supplied with increase and decrease, respectively, of pressure in the mixing chamber, and means for increasing and decreasing the difi'erence between the pressure in the mixing chamber and the pressure under which the fuel liquidis supplied with increase and decrease, respective y, the mixing chamber.

2. An apparatus for supplying a continuous flow under pressure greater than atmosphere of an explosive gaseous mixture of compressed air and the vapor of llquid fuel, comprlsmg a mixing chamber having an air inlet and a mixture outlet, means for sup-' plying compressed air to the mixing chamber through the air inlet, means for su plying volatile liquid fuel to the mixing c amber under a maintained pressure greater than the air pressure in the mixing chamber, means for increasing and decreasing the pressure under which the fuel liquid is supplied with increase and decrease, respectively, of pressure in the mixing chamber,

of air flow through means for increasing and decreasing the difference between the pressure 1n the mixing chamber and the pressureunder which the fuel liquid is supplied with increase and de: crease, respectively, of air flow through the mixing chamber, and adjusting means for varying .said pressure difference independently of change in air flow through the mixing chamber.

3. An apparatus for supplying a continuous flow under pressure greater than atmosphere of an explosive gaseous mixture of compressed air and the vapor of liquid fuel, comprising a mixing chamber having an air inlet and a mixing outlet, means for supplying compressed air to the mixing chamber through the air inlet, means for supplying volatile liquid fuel to the mixing chamber under a maintained pressure greater than the air pressure in the mixing chamber, means for increasing and decreasing the pressure under which the fuel liquid is supplied with increase and decrease, respectively. of pressure in the mixing chamber, means for increasing and decreasing the difference between the pressure in the mixing chamber and the pressure under which the fuel liquid is supplied with increase and decrease. respectively, of air flow through the mixing chamber. and automatically operated means for modifying the variations in said pressure difference under variations in air flow through the mixing chamber.

4. Apparatus for supplying a continuous flow under pressure greater than, atmos-.

phereof an explosive gaseous mixture of compressed air and the vapor of liquid fuel, comprising a mixing chamber having an air inlet and a mixture outlet. a receptacle for liquid fuel, a passage leading from said receptacle and ending in a nozzle set to discharge into the mixing chamber, means for supplying compressed air to the mixing chamber through the air inlet, means for increasing and decreasing the pressure on the fuel liquid in the receptacle with increase and decrease, respectively, ofpressure in the mixing chamber, and means for maintaining a difference between the pressure in the mixing chamber and the pressure on the fuel liquid with the greater pressure on the fuel liquid and for increasing and decreasin such pressure difi'erence with increase an decrease of air flow through the mixing chamber.

5. Apparatus for supplying a continuous flow under pressure greater than atmosphere said recepthrough the air inlet, means for increasing and decreasing the ressure on the fuel liq- .uid in the receptac e with increase and decrease, respectively, of pressure in the mixing chamber, means for maintaining a difference between the pressure in the mixin chamber and the pressure on the fuel liqui with the greater pressure on the fuel liquid and for increasing and decreasing such pressure difference wlth increase and decrease of air flow through the mixing chamber, and means controlled according to such pres sure difference for by-passing air to a point beyond said nozzle to dilute the mixture and to reduce excessive pressure difierence.

6. Apparatus for supplying a continuous flow under pressure greater than atmosphere of an explosive gaseous mixture of compressed air and the vapor of liquid fuel, comprising a mixing chamber. a receptacle for liquid fuel, a passage leading from said receptacle and ending in a nozzle set to discharge into the mixing chamber, an

adjustable valve controlling said nozzle,

means for supplying air under pressure to the mixing chamber, an oif-take leading from the mixing chamber, means for increasing and decreasing the .pressure on the fuel liquid in the receptacle with increase and decrease. respectively, of pressure in the mixing chamber, and means for maintaining a difference between the pressure in the mixing chamber and the pressure on the fuel liquid with the greater pressure on the fuel liquid and for increasing and decreasing such pressure difference with increase and decrease of air flow through the mixing chamber. 1

7. Apparatus for supplying a continuous flow'under pressure greater than atmosphere of an explosive gaseous mixture of compressed air and the vapor of liquid fuel, comprising a mixing chamber. a receptacle for liquid fuel, a passage leading from said receptacle and ending in a nozzle set to discharge into the mixing chamber, an ofi-take leading from the mixing chamber, a source of supply of compressed air in communication respectively with said receptacle and with the mixing chamber, and a pressure reducing restricted orifice between said source of air supply and the mixing chamber. whereby the pressure in the mixing chamber is maintained less than the pressure of the source of supplv of compressedair and the pressure in said receptacle, and whereby such difference in pressures is caused to increase and decrease with increase and decrease, respectively, of air flow through the mixing chamber.

8. Apparatus for supplying a continuous flow under pressure greater than atmosphere of an explosive gaseous mixture of compressed air'and the vapor of liquid fuel, comprising a mixing chamber, a receptacle the air chamber, means roviding communication between the air 0 amber and said receptacle, and a pressure reducing restrlcted orifice for the passage of air from'the air chamber to the mixin chamber, whereby the pressure in the mixing chamber will be less than the pressure in the air chamber and in said receptacle, and whereby the difference between such pressures will be caused 1 to increase and decrease with increase and decrease, respectively, of air flow through the mixing chamber.

9. Apparatus for supplying a continuous flow under ressure greater than atmosphere v of an exp osive gaseous mixture of compressed air and the vapor of liquid fuel, com

rising a mixing chamber, a receptacle for iquid fuel, a passage leading from said receptacle and ending in'a nozzle set to discharge into the mixing chamber, an off-take leading from the mixing chamber, an air chamber of comparatively large size, a supply inlet for supplying air under pressure to the air chamber, means providing communication between the air chamber and said receptacle, a pressure reducing restricted orifice for the passage of air from the air chamber to the mixing chamber, whereby the pressure in the mixing chamber will be less than the pressure in the air chamber and in said receptacle, and whereby the diflerence between such pressures will be caused to increase and decrease with increase and decrease, respectively, of air flow 10. Apparatus for supplying a continuous flow under pressure greater than atmosphere of an explosive gaseous mixture of compressed air and the vapor of liquid fuel, comprising a mixing chamber, a receptacle for liquid fuel, a passage leading from said receptacle and ending in a nozzle set to discharge into the mixing chamber, an oif-take leading from the mixing chamber, an air chamber of comparatively large size, a supply inlet for supplying air-under pressure to the air chamber, means providing communication between the air .chamber and said receptacle, a pressure reducing restricted orifice for the passage of air from the air chamber to the mixing chamber, whereby the pressure in the mixing chamber will be less than the pressure in the air chamber and in said receptacle, and whereby the difierence between such pressures will be caused to increase and decrease with increase and decrease, respectively, of air flow through the mixing chamber, and a passage for by-passing air from the air chamber to a point beyond the nozzle controlled automatically to reduce the increase in such difference in pressures with increasing air flow through the mixing chamber.

In testimony whereof I have hereunto set my hand 1n the presence of two subscribing witnesses.

CHARLES E. LUCKE. Witnesses:

W. S. CALDWELL, A. L. KENT. 

